Dry cell



Oct. 3, 1950 KELLER 2,524,668

DRY CELL Filed June 18, 1946 PatentedOct. 3, 1.9560- UNITED STA FATE DRY CELL Application June 18, 1946, Serial No. 677,457

This invention relates to dry cells of the type commonly known as flashlight batteries.

An object of this invention is a highly eflicient dry cell in which the possibility of leakage of electrolyte is reduced to a minimum.

Other objects, novel features and advantages of this invention will become apparent from the following specification and accompanying drawings, wherein:

Fig. 1 is an elevation partly broken away-oi a dry cell embodying the invention;

Fig. 2 is a section on the line 22 of Fig. 1, and

Fig. 3 is a fragmentary view similar to Fig. 1 illustrating a modification.

A zinc anode cup In is contained in a snugly fitting plastic material shell II having at one end an inwardly extending integral annular flange I2 on which rests the bottom of the cup I6. Preferred plastic materials are ethyl cellulose or cellulose acetate-butyrate thermoplastic molding compound known as Tenite 11. Many other plastics such as phenolic plastics known as Bakelite or the like may be used instead. Within the cup I is contained a bobbin I3 centrally of which is arranged a carbon rod electrode I4. The bobbin I3 is centralized in the cup III by a bottom washer I5 and is surrounded with the usual electrolyte I6 extending up to the top of the bobbin.

A paper disk I'I snugly fits the electrode I4 and extends to the inner surface of the cup III, the disk being spaced from the top of the bobbin I3 to provide an air'chamber. Above the disk I! is provided a sealing compound layer I8 and a second paper disk I9 mounted on the electrode I4 in contact with the upper surface of the sealing compound layer I8 engages the rim of the cup I0.

- The shell II is closed by a cover consisting of a brass cap 2I receiving the upper end of the electrode I4 and a steel annulus 22 mechanically attached to the cap 2| with a collar 23 of suitable plastic insulating material interposed be; tween the cap and the annulus. The periphery 2 Claims. (01. 136-133) of the annulus 22 is spun onto the rim of the shell sections so as to provide a brass terminal without requiring that the whole cover be made of brass. However, it is to be understood that the invention contemplates a one-piece metal cover as well as the two-piece cover illustrated.

In the modification of Fig. 3, the rod electrode I4 is capped by a fiangeless terminal 25 and a metal annulus 26 has its periphery spun onto the rim of the shell II to form a mechanical liquidtight seal therewith. The inner edge of the annulus 26 is oiiset as at 21 for engagement with the washer I9. The annulus 26 is supported by the shell I I in such a manner that the ofiset edge 21 is pressed tightly against the washer I9 by the resiliency of the annulus, thereby forming a seal between the inner edge of the annulus 26 and the washer I9.

I claim:

1. A leak resistant battery construction comprising a plastic material shell open at one end and having an inwardly extending integral annular flange at its other end defining an opening in said other end, a metal cup anode resting on said flange and having its bottom exposed through said opening in said other end of said shell to facilitate direct electrical contact with the said bottom of said metal cup anode, a bobbin within said cup. containing a central rod electrode, an insulating disk snugly fitting said central rod electrode, a sealing compound layer in said cup anode, overlying said disk, a second disk of insulating material surrounding said rod electrode and overlying said layer of sealing compound, a cap receiving the upper end of the rod electrode and having an annular flange, a metallic cover having an opening through which said cap projects, the edge of said cover defining said opening overlying said annular flange of said cap, and a collar of insulating material interposed between the cover and said cap and lying on the annular flange of the latter to insulate the cap from the cover and to provide a seal, said cover having its outer periphery crimped tightly over the rim of the plastic material shell at its first-named end to secure it to said shell and to form a mechanical seal therewith.

2. A leak resistant battery construction comprising a plastic material shell open at one end and having an inwardly extending integral annular flange at its other end defining an opening in said other end, a metal cup anode resting on said flange and having its bottom exposed through said opening in said other end of said shell to facilitate direct electrical contact with the said bottom of said metal cup anode, a bobbin within said cup containing a central rod electrode, an insulating disk snugly fitting said central rod electrode and extending to the inner surface of said cup anode, a sealing compound layer in said cup anode overlying said disk, 2. second disk of insulating material surrounding said rod electrode and overlying said layer of sealing compound and resting on the rim of said cup anode, a, cap receiving the upper end of the rod electrode, a metallic cover having an opening through which said cap projects, the inner edge of said cover defining said opening being offset and pressed tightly against said second disk to provide a seal between the inner edge of said cover and said disk, and said cover having its outer periphery crimped tightly over the rim of the plastic material shell at its first-named end to secure it to said shell and to form a mechanical seal therewith.

FREDERICK A. KELLER.

4 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,000,510 Corigliano May 7, 1935 2,060,796 Cahoon Nov. 17, 1936 2,060,832 Smith Nov. 17, 1936 2,315,592 Cargill Apr. 6, 1943 2,332,456 McEachron et a1. Oct. 19, 1943 2,392,795 Anthony et a1 Jan. 8, 1946 2,399,089 Anthony Apr. 23, 1946 2,427,561 Keller Sept. 16, 1947 2,445,005 Schmelzer July 13, 1948 

1. A LEAK RESISTANT BATTERY CONSTRUCTION COMPRISING PLASTIC MATERIAL SHELL OPEN AT ONE END AND HAVING AN AWARDLY EXTENDING INTEGRAL ANNULAR FLANGE AT ITS OTHER ENDS DEFINING AN OPENING IN SAID OTHER END, A METAL CUP ANODE RESTING ON SAID FLANGE AND HAVING ITS BOTTOM EXPOSED THROUGH SAID OPENING IN SAID OTHER END OF SAID SHELL TO FACILITATE DIRECT ELECTRICAL CONTACT WITH THE SAID BOTTOM OF SAID METAL CUP ANODE, A BOBBIN WITHIN SAID CUP CONTAINING A CENTRAL ROD ELECTRODE, AN INSULATING DISK SNUGLY FITTING SAID CENTRAL ROD ELECTRODE, A SEALING COMPOUND LAYER IN SAID CUP ANODE OVERLYING SAID DISK, A SECOND DISK OF INSULATING MATERIAL SURROUNDING SAID ROD ELECTODE AND OVERLYING SAID LAYER OF SEALING COM- 